1. Field of the Invention
The present invention relates to a silicon member, which is placed in a semiconductor manufacturing apparatus, a heat treatment apparatus, or the like, and used in a condition where it is heated, and a method of producing the silicon member.
Priority is claimed on Japanese Patent Application No. 2013-067952, filed Mar. 28, 2013, the contents of which are incorporated herein by reference.
2. Description of Related Art
Conventionally, when panels such as the liquid crystal are manufactured, the deposition treatment or the heat treatment is performed on the panels occasionally. In the deposition and heat treatments, a holding plate for holding the panel is needed. Conventionally, quartz, which is inexpensive and has excellent heat resistance, has been used as the holding plate. However, quartz has a poor thermal conductivity; making it difficult for the entire panel to be heated evenly. Therefore, usage of quartz as the holding plate causes a deteriorate in-plate uniformity, which leads to possible reduction of quality and yield. In addition, in order to improve quality by equalizing the temperature within a predetermined range, it is necessary to set a longer period of time for the pre-deposition process and the heat treatment itself, which leads to a reduced productivity.
For example, in order to circumvent the above-mentioned problem, usage of silicon plate as the holding plate for holding panels is disclosed recently in Patent Literature 1 (PTL 1) (Japanese Unexamined Patent Application, First Publication No. 2008-138986). Since thermal conductivity of the silicon plate is higher than that of quartz, the overall temperature uniformity is improved. Thus, usage of the silicon plate has advantages, such as characteristics at the central and outer peripheral parts being almost equal, during manufacturing a large-sized panel.
Also, in addition to the above-mentioned silicon plate, large numbers of silicon members which are used in the condition where they are heated at a high temperature, such as the silicon ring material, silicon disc material, silicon plate material, or the like placed in the semiconductor manufacturing apparatus, and the silicon-made rectangular pillar material, bar material, bulk material, or the line used in the heat treatment apparatus, are provided. One of the reasons for the usage of them is that the silicon members have a higher thermal conductivity than quartz-made members.